Marissa Mayer is on an insane acquisition spree as she tries to breathe life into Yahoo.

In this month alone, she's hoovered up four companies. Since she took over a year ago, she's bought 18 different companies, according to Wikipedia. (We checked Wikipedia against Yahoo's official Twitter feed which announced all the deals.)

Her old company, Google, was a prolific acquirer, which must have been an influence over her style.

We've assembled the companies here to try to make some sense of her scattershot approach to rebuilding Yahoo.